*: remove THREAD_ON macros, add nullity check

The way thread.c is written, a caller who wishes to be able to cancel a
thread or avoid scheduling it twice must keep a reference to the thread.
Typically this is done with a long lived pointer whose value is checked
for null in order to know if the thread is currently scheduled.  The
check-and-schedule idiom is so common that several wrapper macros in
thread.h existed solely to provide it.

This patch removes those macros and adds a new parameter to all
thread_add_* functions which is a pointer to the struct thread * to
store the result of a scheduling call. If the value passed is non-null,
the thread will only be scheduled if the value is null. This helps with
consistency.

A Coccinelle spatch has been used to transform code of the form:

  if (t == NULL)
    t = thread_add_* (...)

to the form

  thread_add_* (..., &t)

The THREAD_ON macros have also been transformed to the underlying
thread.c calls.

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

1 files changed, 25 insertions, 24 deletions

diff --git a/zebra/zebra_ptm.c b/zebra/zebra_ptm.c
index bc924842d..85f3efae8 100644
--- a/zebra/zebra_ptm.c
+++ b/zebra/zebra_ptm.c
@@ -182,12 +182,13 @@ zebra_ptm_flush_messages (struct thread *thread)
       close(ptm_cb.ptm_sock);
       ptm_cb.ptm_sock = -1;
       zebra_ptm_reset_status(0);
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                            NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return (-1);
     case BUFFER_PENDING:
-      ptm_cb.t_write = thread_add_write(zebrad.master, zebra_ptm_flush_messages,
-                                        NULL, ptm_cb.ptm_sock);
+      ptm_cb.t_write = thread_add_write(zebrad.master,
+                                        zebra_ptm_flush_messages, NULL,
+                                        ptm_cb.ptm_sock, NULL);
       break;
     case BUFFER_EMPTY:
       break;
@@ -207,15 +208,15 @@ zebra_ptm_send_message(char *data, int size)
       close(ptm_cb.ptm_sock);
       ptm_cb.ptm_sock = -1;
       zebra_ptm_reset_status(0);
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                            NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return -1;
     case BUFFER_EMPTY:
       THREAD_OFF(ptm_cb.t_write);
       break;
     case BUFFER_PENDING:
-      THREAD_WRITE_ON(zebrad.master, ptm_cb.t_write,
-		      zebra_ptm_flush_messages, NULL, ptm_cb.ptm_sock);
+      thread_add_write(zebrad.master, zebra_ptm_flush_messages, NULL,
+                       ptm_cb.ptm_sock, &ptm_cb.t_write);
       break;
     }
 
@@ -234,8 +235,8 @@ zebra_ptm_connect (struct thread *t)
 
   if (ptm_cb.ptm_sock != -1) {
     if (init) {
-      ptm_cb.t_read = thread_add_read (zebrad.master, zebra_ptm_sock_read,
-                                      NULL, ptm_cb.ptm_sock);
+      ptm_cb.t_read = thread_add_read(zebrad.master, zebra_ptm_sock_read,
+                                      NULL, ptm_cb.ptm_sock, NULL);
       zebra_bfd_peer_replay_req();
     }
     zebra_ptm_send_status_req();
@@ -245,8 +246,8 @@ zebra_ptm_connect (struct thread *t)
     if (ptm_cb.reconnect_time > ZEBRA_PTM_RECONNECT_TIME_MAX)
       ptm_cb.reconnect_time = ZEBRA_PTM_RECONNECT_TIME_MAX;
 
-    ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect, NULL,
-					 ptm_cb.reconnect_time);
+    ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect, NULL,
+                                      ptm_cb.reconnect_time, NULL);
   } else if (ptm_cb.reconnect_time >= ZEBRA_PTM_RECONNECT_TIME_MAX){
     ptm_cb.reconnect_time = ZEBRA_PTM_RECONNECT_TIME_INITIAL;
   }
@@ -653,14 +654,14 @@ zebra_ptm_sock_read (struct thread *thread)
       close (ptm_cb.ptm_sock);
       ptm_cb.ptm_sock = -1;
       zebra_ptm_reset_status(0);
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                         NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return (-1);
     }
   }
 
-  ptm_cb.t_read = thread_add_read (zebrad.master, zebra_ptm_sock_read,
-                                  NULL, ptm_cb.ptm_sock);
+  ptm_cb.t_read = thread_add_read(zebrad.master, zebra_ptm_sock_read, NULL,
+                                  ptm_cb.ptm_sock, NULL);
 
   return 0;
 }
@@ -697,8 +698,8 @@ zebra_ptm_bfd_dst_register (struct zserv *client, int sock, u_short length,
 
   if (ptm_cb.ptm_sock == -1)
     {
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                             NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return -1;
     }
 
@@ -854,8 +855,8 @@ zebra_ptm_bfd_dst_deregister (struct zserv *client, int sock, u_short length,
 
   if (ptm_cb.ptm_sock == -1)
     {
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                             NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return -1;
     }
 
@@ -976,8 +977,8 @@ zebra_ptm_bfd_client_register (struct zserv *client, int sock, u_short length)
 
   if (ptm_cb.ptm_sock == -1)
     {
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                             NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return -1;
     }
 
@@ -1026,8 +1027,8 @@ zebra_ptm_bfd_client_deregister (int proto)
 
   if (ptm_cb.ptm_sock == -1)
     {
-      ptm_cb.t_timer = thread_add_timer (zebrad.master, zebra_ptm_connect,
-                                             NULL, ptm_cb.reconnect_time);
+      ptm_cb.t_timer = thread_add_timer(zebrad.master, zebra_ptm_connect,
+                                        NULL, ptm_cb.reconnect_time, NULL);
       return;
     }